The UK's equal pay legislation needs a major overhaul, a leading authority on human rights law has said.

Professor Aileen McColgan told File On 4 the law was out of date, particularly in light of court judgements which placed huge costs on local councils.

She said the government had been "tinkering" with the system rather than seeking major reform.

Local Government Minister John Healey said councils were making real progress in implementing equal pay.

Prof McColgan, who is also a barrister with the Matrix Chambers, told the BBC when equal pay legislation was introduced more than 30 years ago it dealt primarily with women doing the same jobs as men but receiving less pay.

Claims avalanche

But most cases now centre on women doing predominanly female jobs comparing themselves with men doing traditional male work and the legislation is not designed to cope with these kind of cases.

A European ruling in 2004, entitled women to six years' back pay, unleashing an avalanche of claims.

Local authorities and other public sector employers face massvie increases in their wage bills and claims for back pay following legal rulings affecting thousands of low paid women.

As some councils have tried to reform their pay structures it has sparked angry reactions from trade unions such as in Birmingham where council workers went on strike earlier this month over pay restructuring.

Prof McColgan said central government must bear part of the blame for the crisis in equal pay.

'Pay paralysis'

"There's a sort of paralysis around equal pay but I think there has been a paralysis arouond equal pay for 35 and more years, it is so complicated and the stakes are so high.....huge amounts of money turn on these cases," she said.

"The government has maintained this line that there isn't anything fundamentally problematic about the equal pay system," the academic added.

Nobody from the government would be interviewed but a written statement from Mr Healey said that councils can borrow £660 million to spread the costs and settle claims more quickly, and more will be offered next year.

He added: "Councils are making real progress on implementing equal pay but progress and determination still varies in different areas, and I want to see more authorities tackle this in an active and affordable manner."

Hear the full story on BBC Radio 4: File On 4 Tuesday 12 February at 2000 GMT, repeated Sunday 17 February at 1700 GMT or online at File on 4 website.